You're about to meet families that made huge sacrifices for their kids. They invested hundreds of hours and thousands of dollars. And in some cases, rearranged their entire lives. All for cheerleading. These young athletes are superstars on social media, where legions of fans follow their every move. Now, it's game time. ABC's bianna golodryga headed out with them to the competition of their lives. The hair is part of the show. Reporter: Today, gabby butler and her mom need every hair to be perfectly in place. She's hungry. She's tired. Reporter: Meanwhile -- . Reporter: Michael Eddie is terrified he might miss the most important moment of his life. I guess it's just -- The fact this is my last intensifies everything. Right now, is basically do or die. Reporter: For Carly manning, the pressure is almost too much. I wouldn't want to disappoint people by giving up. Reporter: For these three world class athletes, thousands of hours of training and problems with injuries have led up to this one day. Welcome to the world championships of competitive cheerleading. Do you believe in you? Yes. Do you believe in us. We are -- The best of the best. We are -- Wildcats. Reporter: No pom-poms in sight. Here the risk is high. And the stakes are even higher. Any given moment, something can happen. Reporter: A single miss can cost the athletes and their families everything they've worked for. I'm a mom that loves her kids above and beyond. And I would do whatever they want. Reporter: Our story begins in this Texas gym, two months before the world championships. Where 15-year-old Carly manning has been training more than half her life. This year, for the first time, she's made it on to the wildcats. They compete at the most advanced levels. Practices are very important. Especially here. That's where you're trying to earn your spot. We're all just trying to push to be on the team. Reporter: Her team is hoping that Carly's ability to fly the record-breaking heights like this will help them win back-to-back championships. And it's not a bad bet. Those are the medals that I've won over the years. Reporter: Carly's room is decorated with proof of her stellar track record. But for all these wins, this teenager had to make some sacrifices. I haven't watched TV in I can't tell you how long. I think it's years. Reporter: Very busy years, filled with very busy days. Most like this one, start at 6:00 A.M. I have about 16-hour days. Reporter: First, school. And off to practice. Basically, this is only opportunity I have to do homework unless I want to stay up really late when I get home. Reporter: To make all this possible, she needs a chauffeur. Carly spends as much time cheerleading as someone would in a full-time job. Reporter: Carly's mom spends 16 hours on the road every week because of cheer. Several times I have to remind Carly, hey, I'm doing this for you. Reporter: And with just a week to go before the world championships, the schedule is about to get way more intense. And so are the practices. You come in here for the practices, including if you have mono, if you have strep. If you have a broken leg, kicking out the side of your body, you have a smile on your face and you fake it the entire practice. You can do it. Okay. You can do it. Flipping, spinning, throwing girls in the air. That's the dangerous part of clear he'ding. I broke my right ankle. I had various hamstring injuries. Going to do it till my body breaks. Reporter: Her mom, however, does believe this sacrifice does serve a purpose. She learns so many lessons. She learns how to have a great work ethic. How to fully commit to something, which she does do. Reporter: Carly is, after all, a straight-a student. But Cindy worries her daughter might be taking this dream too far. It's about 11:20 P.M. Now. We're just getting home. If I had to give up cheer or give up school, I would give up school. What about your life? I don't know. That makes no sense. I don't know. I want to cheer. Cheer where? True. Okay. Reporter: Competitive cheer is a short-lived career. She can't go pro or win olympic glory. But surprisingly, Carly has become a celebrity of sorts with almost 500,000 followers on instagram. That number to me is mind-blowing. Oh, my gosh. Reporter: Gabby butler is also a celebrity. She even has groupies. It's such a nice feeling, like, in my heart. It really does make me feel good, even though sometimes I'll get a little annoyed. Or I'll feel like overwhelmed. Reporter: This is not what drives her to keep flipping. I love performing and just doing my best. And being with my team. And making memories out of it. Reporter: And she has a lot of them. She's been cheering since she was eight. This Florida girl was recruited by one of the most elite teams in the country. Based in California. Gabby is addicted to cheer. She loves it from her soul. It's like her oxygen. Reporter: To further gabby's cheer dreams, her mother made a difficult decision to split up the family. Moving across the country, leaving her husband and two other children behind. Living away from my husband and my children is extremely hard. We're a tight-knit family. It's putting our hearts on the other side of the country. I think it's funny how you hate doing your hair. Reporter: Their home away from home has become an accidental cheer house. Debbie is den mom to a handful of teenagers at any given time. Here, they eat, breathe and sleep cheer. But it's pretty tight quarters. They're all forced to get very close. Sometimes Debbie has to sleep on the couch. I'm a mom. Not a cheer mom. A mom who loves her kids above and beyond. I will do whatever they want. We need to finish this. Reporter: In order to raise a star like gabby, she must manage every last detail of her daughter's life. From what to pack. I don't work. This is my job. Reporter: To the color of her nails. Let me see. Just a little more. They tumble. You know what tumbling is? If it was up to me, cheerleading would be slicked-back ponytail with natural makeup. Reporter: Unfortunately for gabby and her mom, cheer involves a lot of primping. Can you not touch my face. My back is out. You know this. And if I have to move, your head one more time, I'm not going to do it anymore. I can honestly say I have fought more with my children than anything, over hair. No. Reporter: And it's taken more than just an emotional toll. How much money would you say over the years, you've spent on supporting your daughter in cheer. We're in the hundreds of thousands. Reporter: A lot of the money is spent on traveling to competitions. Luckily for this cheer family that's split across the country, it's a perfect excuse for a reunion. I'm seeing my dad and my sister for the first time. I haven't seen them in like forever. It's very much about being together as a family. And the time, supporting each other. We make a big sacrifice. We're doing it because we love it. Reporter: Gabby is getting made up yet again. This time, for a photo shoot, where she meets up with Carly. I always wanted to meet you, too. Reporter: They can be casualties of their own fame. People do definitely see things on instagram and Twitter and jump to conclusions really fast. That comes with stories and rumors and things like that. Reporter: Carly and her boyfriend, Matt, are the reigning cheer couple online, with sites dwoed devoted to their relationship. I used to be at magazines and say, I can't believe she did that. Until I was in this situation, where I was under a little microscope. Reporter: But they are still kids, exposed to the danger that can come with this kind of attention. When you read comments, that people say, get in my bed -- That's a little over the edge. Reporter: Does it bother you that there's so much sexualization of the sport? Cheerleading is one of the most sexual sports. You have cheerleaders walking around in half-tops with their stomachs showing. We don't dress that we for attention. We dress that way because that's our wardrobe. I love him being a cheerleader. Reporter: Michael is also a budding celebrity. But he's not your typical cheerleader. He's a football player. But he was better than the cheerleaders that were cheering for him. I've done so many sports. This is the hardest sports I've ever done. Reporter: He actually turned to cheer because of football. Wanted to do a back flip if I scored a touchdown. Football is like a brotherhood. But cheer is performing. It's doing it in front of a crowd and feeling like a rock star for 2:30. Reporter: Being a male cheerleader has its challenges. I didn't want anybody to know I was a cheerleader. If anyone asks me, I'm going to own up to it. Reporter: Michael Eddie's family had little trouble accepting his decision. They were already a cheer family. His sister was, in part, his inspiration. Cheer was the thing that girls did. Once my son was involved -- I saw the conditioning that they had in the cheer program. I developed a lot of respect. For cheer. Reporter: Now, at 19, Michael Eddie is about to age out of his team. So, the upcoming world championships are his final hoorah. Got a third-consecutive world title I want to win. I have to be a good leader on my team. Come on. Everyone's coming. Don't want to be distracted right now. This is my last year. I want to make it solid. Reporter: For gabby and Michael Eddie, it's their last chance to practice at home before they have to defend their world title. Do you guys want to end? Do you want to feel confident? But they're not looking like the champions they're known to be. There's no reason this stuff should be falling. Reporter: After three mistakes, coach Eddie had had enough. Three mistakes in one section is not acceptable. I can cool off a little bit, as well. Definitely punishment. It's about getting to the finish line.

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